[monitoring] fix: use retrying module in the fixture class (#3285)

* fix: use retrying module in the fixture class

fixes #2971
fixes #2972
fixes #2973
fixes #3085

It will likely fix those issues, not guaranteed, but it's worth a try.

Author: Takashi Matsuo

monitoring/api/v3/alerts-client/requirements-test.txt

@@ -1 +1,2 @@
 pytest==5.3.2
+retrying==1.3.3

monitoring/api/v3/alerts-client/snippets_test.py

@@ -17,9 +17,11 @@
 import random
 import string
 
+from google.api_core.exceptions import Aborted
 from google.cloud import monitoring_v3
 import google.protobuf.json_format
 import pytest
+from retrying import retry
 
 import snippets
 
@@ -29,6 +31,10 @@ def random_name(length):
         [random.choice(string.ascii_lowercase) for i in range(length)])
 
 
+def retry_if_aborted(exception):
+    return isinstance(exception, Aborted)
+
+
 class PochanFixture:
     """A test fixture that creates an alert POlicy and a notification CHANnel,
        hence the name, pochan.
@@ -42,30 +48,40 @@ def __init__(self):
             monitoring_v3.NotificationChannelServiceClient())
 
     def __enter__(self):
-        # Create a policy.
-        policy = monitoring_v3.types.alert_pb2.AlertPolicy()
-        json = open('test_alert_policy.json').read()
-        google.protobuf.json_format.Parse(json, policy)
-        policy.display_name = 'snippets-test-' + random_name(10)
-        self.alert_policy = self.alert_policy_client.create_alert_policy(
-            self.project_name, policy)
-        # Create a notification channel.
-        notification_channel = (
-            monitoring_v3.types.notification_pb2.NotificationChannel())
-        json = open('test_notification_channel.json').read()
-        google.protobuf.json_format.Parse(json, notification_channel)
-        notification_channel.display_name = 'snippets-test-' + random_name(10)
-        self.notification_channel = (
-            self.notification_channel_client.create_notification_channel(
-                self.project_name, notification_channel))
+        @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+               stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+        def setup():
+            # Create a policy.
+            policy = monitoring_v3.types.alert_pb2.AlertPolicy()
+            json = open('test_alert_policy.json').read()
+            google.protobuf.json_format.Parse(json, policy)
+            policy.display_name = 'snippets-test-' + random_name(10)
+            self.alert_policy = self.alert_policy_client.create_alert_policy(
+                self.project_name, policy)
+            # Create a notification channel.
+            notification_channel = (
+                monitoring_v3.types.notification_pb2.NotificationChannel())
+            json = open('test_notification_channel.json').read()
+            google.protobuf.json_format.Parse(json, notification_channel)
+            notification_channel.display_name = (
+                'snippets-test-' + random_name(10))
+            self.notification_channel = (
+                self.notification_channel_client.create_notification_channel(
+                    self.project_name, notification_channel))
+        setup()
         return self
 
     def __exit__(self, type, value, traceback):
         # Delete the policy and channel we created.
-        self.alert_policy_client.delete_alert_policy(self.alert_policy.name)
-        if self.notification_channel.name:
-            self.notification_channel_client.delete_notification_channel(
-                self.notification_channel.name)
+        @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+               stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+        def teardown():
+            self.alert_policy_client.delete_alert_policy(
+                self.alert_policy.name)
+            if self.notification_channel.name:
+                self.notification_channel_client.delete_notification_channel(
+                    self.notification_channel.name)
+        teardown()
 
 
 @pytest.fixture(scope='session')
@@ -81,36 +97,55 @@ def test_list_alert_policies(capsys, pochan):
 
 
 def test_enable_alert_policies(capsys, pochan):
-    snippets.enable_alert_policies(pochan.project_name, False)
-    out, _ = capsys.readouterr()
+    @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+           stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+    def invoke_sample(val):
+        snippets.enable_alert_policies(pochan.project_name, val)
 
-    snippets.enable_alert_policies(pochan.project_name, False)
+    invoke_sample(False)
+    invoke_sample(False)
     out, _ = capsys.readouterr()
     assert "already disabled" in out
 
-    snippets.enable_alert_policies(pochan.project_name, True)
+    invoke_sample(True)
     out, _ = capsys.readouterr()
     assert "Enabled {0}".format(pochan.project_name) in out
 
-    snippets.enable_alert_policies(pochan.project_name, True)
+    invoke_sample(True)
     out, _ = capsys.readouterr()
     assert "already enabled" in out
 
 
 def test_replace_channels(capsys, pochan):
-    alert_policy_id = pochan.alert_policy.name.split('/')[-1]
-    notification_channel_id = pochan.notification_channel.name.split('/')[-1]
-    snippets.replace_notification_channels(
-        pochan.project_name, alert_policy_id, [notification_channel_id])
+    @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+           stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+    def invoke_sample():
+        alert_policy_id = pochan.alert_policy.name.split('/')[-1]
+        notification_channel_id = pochan.notification_channel.name.split(
+            '/')[-1]
+        snippets.replace_notification_channels(
+            pochan.project_name, alert_policy_id, [notification_channel_id])
+
+    invoke_sample()
     out, _ = capsys.readouterr()
     assert "Updated {0}".format(pochan.alert_policy.name) in out
 
 
 def test_backup_and_restore(capsys, pochan):
-    snippets.backup(pochan.project_name, 'backup.json')
+    @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+           stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+    def invoke_backup():
+        snippets.backup(pochan.project_name, 'backup.json')
+
+    invoke_backup()
     out, _ = capsys.readouterr()
 
-    snippets.restore(pochan.project_name, 'backup.json')
+    @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+           stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+    def invoke_restore():
+        snippets.restore(pochan.project_name, 'backup.json')
+
+    invoke_restore()
     out, _ = capsys.readouterr()
     assert "Updated {0}".format(pochan.alert_policy.name) in out
     assert "Updating channel {0}".format(
@@ -119,8 +154,14 @@ def test_backup_and_restore(capsys, pochan):
 
 def test_delete_channels(capsys, pochan):
     notification_channel_id = pochan.notification_channel.name.split('/')[-1]
-    snippets.delete_notification_channels(
-        pochan.project_name, [notification_channel_id], force=True)
+
+    @retry(wait_exponential_multiplier=1000, wait_exponential_max=10000,
+           stop_max_attempt_number=5, retry_on_exception=retry_if_aborted)
+    def invoke_delete():
+        snippets.delete_notification_channels(
+            pochan.project_name, [notification_channel_id], force=True)
+
+    invoke_delete()
     out, _ = capsys.readouterr()
     assert "{0} deleted".format(notification_channel_id) in out
     pochan.notification_channel.name = ''   # So teardown is not tried